Towards Super-resolution via Iterative multi-exposure Coaddition

TL;DR

This paper introduces a novel iterative multi-exposure coaddition method with a ratio-correction term that accelerates convergence and enhances super-resolution, benefiting astronomical imaging and weak lensing analysis.

Contribution

The proposed method incorporates a ratio-correction term for faster convergence in super-resolution from multi-exposure images, improving accuracy over previous techniques.

Findings

Enhanced signal-to-noise ratio in coadded images

Improved accuracy in source flux and morphology measurements

Better performance in faint source detection and weak lensing analysis

Abstract

In this article, we provide an alternative up-sampling and PSF deconvolution method for the iterative multi-exposure coaddition. Different from the previous works, the new method has a ratio-correction term, which allows the iterations to converge more rapidly to an accurate representation of the underlying image than those with difference-correction terms. By employing this method, one can coadd the under-sampled multi-exposures to a super-resolution and obtain a higher peak signal-to-noise ratio. A set of simulations show that we can take many advantages of the new method, e.g. in the signal-to-noise ratio, the average deviation of all source fluxes, super-resolution, and source distortion ratio, etc., which are friendly to astronomical photometry and morphology, and benefits faint source detection and shear measurement of weak gravitational lensing. It provides an improvement in fidelity over the previous works tested in this paper.